Brick machinery



F. B. LAMBERT.

BRICK MACHINERY.

APPLICATION FILED ocT.9.1915.

1,358,91 '7, Patented Sept. 28,V 1920.

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1 /f t M t Indien/1507 fram B. La 2967147 'PATENT OFFICE.

FRANK B. LAMBERT, OF CHICAGO, ILLINOIS.

BRICK MACHINERY.

Specification of Letters Patent Patented Sept. 28, 1920.

Application led October 9, 1915. Serial No. 54,935.

i Chicago, in the county of Cook and State .strength of the bricks.

ofIIllinOiS, have invented a certain new and useful Improvement in Brick Machinery, or Y which the following is a full, clear, concise, and eXact description, reference being had to the accompanying drawings, forming a part of this specification. Y My invention relates to brick machinery and more especially toa screw and sleeve for forcing the clay through'the brick-form'- ing-die. y

In practising the process of burning bricks, as set out in my co-pendingapplications, Serial No. 681,720 filed March 5, 1912, and Serial No. 15,910 filed March 20, 1915, I lind that a certain treatment of the clay is desirable in producing the green bricksV so that when relativel f sudden and intense heat is applied `to the bricks, as is practised in accordance with the general process outlined above, the bricks will not be deformed or cracked by expansion and contraction;

The difficulties heretofore experienced in practising said processes have resulted largely from the fact that the clay in the to a greater density than is the clay on the exterior. The present invention aims to provide a machine which will form the bricks with substantially uniform density throughout, or with a slightly greater den sity upon the exterior than in the interior, so that the natural molecular movement, due to contraction and expansion, and such chemical actions as occur during burning, may not destroy or impair the form or In the accompanying drawings, which form a part of the present specification, I have illustrated one embodiment ofV my invention.

Figure 1 is a longitudinal cross section of a machine constructed in accordance with my invention. Y

Fig. 2 is a side elevation, and j Fig. 3 is a front elevation of the teeth or blades for working the clay.

The machine which I have illustrated comprises a main mixing barrel or cylinder 1, provided with an opening 2 at the top for feeding the clay, and a main shaft 3 which carries upon its inner end the screw 4. The main shaft 3 has a squared end 5, which fits into a correspondingly squared recess 6, which is formed' in the screw l.

The screw l is tapered downward toward itsvend and is surrounded byy a shell or screw casing 7, of corresponding form. 'The shell 7 lits closely to the screw l so that the edges of the fins or screw-blade 8, which are formed with an enlarged edge portion 9, fit closely in the shell 7.

The Vshell 7 is mounted in an inclosing casing 10, which is bolted or secured in a suitable manner to the main barrel 1. rFhe reduced end of the casing 7 communicates with a nozzle 11 which discharges the clay through the die 12 in suitable shape to be formed into individual bricks. rlhe space between the casing 7 andthe outer shell 10, is preferably employed as a steam jacket for keeping the casing 7 and the contents thereof, warm. vSimilarly the spa-ce between thev casing 13 and the nozzle 11 is preferably employed as a steam jacket to keep the nozzle 11 warm. The die 12 is preferably lubricated by jets of steam through the openings 14: at the point where the clay passes from the nozzle Yto the die 12.

The driving end of the main shaft 3 has a suitable bearing in or adjacent the main barrel 1, and has a suitable driving wheel, such as a gear-wheel 15, secured thereto, for driving the shaft 3. The shaft 3 is pro`V videdwith a helical row of sockets 16 and 17 for receiving the stems 18 and the blades 19,respectively, of suitable knives or teeth, which serve to work and temper the clay and to move it forward toward the nozzle and the die 12.

Adjacent the discharge end of the main barrel 1, a number of longitudinal ridges, 20, are provided. 'Ihese ridges tend to prevent turning of the mass cf clay and insure that the clay will be moved toward the die opening as the main shaft 13 revolves in the direction indicated by the arrow 21.

Heretofore in the art it has been customary to form the casing 7 with longitudinal ridges, which might be considered as continuations of the ridges 20.

Such longitudinal ridges were employed for the same purpose as the ridges 20, namely, to prevent turning of the mass of clay, and to insure its moving forward. Such construction of longitudinal ridges or grooves has resulted in producing brick of a Character which isV unsuit'ed to vrapid burn ing. Due to thev fact that the friction'between the clay and the walls of the casing- 7 and the die 11, is greater than the friction between adjacent particles of clay* at the center', the center of the mass of clay will be moved outward more rapidly than the edges'. As aresult ofsuch operation, the bricks, when they issue as a ribbon or bar of clay from the die `12, will have a greater 'density at the central part than at the outer part, the result being that whenthese bricks areburned ythey willcontract and expand a greater amount at the center` than they do vat the ouside, and cracking and checking results.

Another disadvantage where the longitudinal grooves are employed is, that the ta# per or slope` of the casing 7 is so great that the clay does not tend readily to moveV along 'these grooves or ridges, being churned up Y at the center and discharged therefrom, Vin

a dense mass with the results above setout.

' According to my invention, longitudinal marked inthe action of the clay as it is propelled toward the nozzle 11 and the die 12. As soon as a particle of clay is caught by the blade S, it will'tend to 'adhere more Vor less tothe blade 8 or the edge9 and as the blade moves forward there will be a slippage between the particle and the blade e, due,'rst of all,1 to the pressure exerted by the teeth or blades' 19 on the main shaft,y

. and dueto the pressure`- exerted by the rest of the screw 4, upon the clay contents in the Y casing 7. In addition, there will be a tend- `ency for the' clay particle or mass to be Vcaught by one of the ridges 2.2,' and lifted away from the blade 8. As la result'the mass or particle of clay will tend to slide along en the ridges 22 land the grooves 23 formed vthere-betweern and will be compressed bybeing forcedinto smaller vspace as the particle or mass approaches'the discharge end of the casing 7. lt canfthus be seen that the particle-or mass'of clay hasa slip, not only with reference to the sc rew 4, but has a slip with reference to the walls Yof the casing 7 lso far as rotation'is concerned. In the prior art devices such rotation was considered absolutely detrimental, and in those structures it rightly IVwould be so. In' theJ Vpresent structure an advantagey 'is gained' byv havingfthe mass of clay rotate to a certain degree, in that compression of the mass of clay voccurs by the clay being vforced from theoutside towardthe center instead of from the center toward the outside.

Compression from the outside is caused primarily by the clay sliding along the .grooves 23 and ridges 22 in moving from the relatively larger spa-Cain the receiving end of the casing 7 toward the discharge end of the casing 7. 'llhe inward movement of the clay isA v'e'ryv gradual, due to the fairly long path through which it iroves in following the spiral grooves 23 and ridges 22,-that is to say, the angle of compression which the clay must travel' is very slight in the device constructed in accordance with my invention, as compared witlrthe angle of travel or compression ofthe devices of the prior art'. The result which is accomplished is a marked improvement over the prior art devices inthat the densityof the bricks is more nearly uniform and may, in fact, be slightly greater at the outside than at the inside. he ideal conditiony is to have the bricks vof a uniform density throughout. The invention .which I have described makes 'it possible to yapproach much nearer the ideal lcondition Ythan has heretofore been known.v

The path of the clay may be described as follows:

The clay enters' at the feedV opening 2 and is worked and tempered by the clay knives 19 and movesl` forward-toward the discharge end of the main barrel l. lt will be noticed that the 'main barrel 1 is tapered to vaccommodate the increasing density of the clay as it is discharged. rlhr'oughout the portion of the barrel occupied by the ridges 20, the clay is preferably moved Y along mostly in an axial direction. lt is ythen discharged to the screw casing 7 where the same is rotatedabout the general axis of movement, namely, the axis ofthe shaft 3, and is simultaneously compressed by pressure applied from vthe outside, and then it is Vdischarged into lthe nozzle 11, where it assumes' a lineal movement and is formed by the die 12.

It can be seen that the above providesV a new fmethod of manipulatingthe clay to Jorin the same into bricks.

'While l have described my invention with reference to the details of a particular mechanism, l wish it to be understood l'that the process which Vl have described may be `carried out in other vi'n'ech'anism than that screw having a single thread of relatively Ylarge pitch, means for rotating the screw,

a screw casing having an inner `surface leo closely approximating the outer edges of the screw, said casing having its inner tapered surface substantially covered by a plurality of shallow screw threads alter nated with grooves of substantially the same Width as the threads.

2.111 a clay press, a sharply tapered screwl having a single thread of relatively 'large pitch7 means for rotating the screw,

a screw casing having an inner surface closely approximating the outer edges of the Nscrew, said casing having its inner tapered surface substantially covered by a plurality of shallow7 screw threads alternated with grooves of substantially the same width as the threads, the side faces of the threads which receive the clay being inclined to the axis of the screw and adapted to direct the clay toward the axis of the casing as the same is forced forward by the screw. K

In witness whereof, I hereuntosubscribe my name this day ci October A. D. 1915.

FRANK B. LAMBERT. 

